There conventionally is technology of driving an oil pump by an engine such as an engine and a motor. For example, Patent Literature 1 discloses technology of an oil pump driving device provided with a first power transmission mechanism which connects an output shaft of an electric motor to a drive shaft of the oil pump and a second power transmission mechanism which connects an output shaft of the engine to the drive shaft of the oil pump with a first one-way clutch allowing only power transmission from the electric motor to the oil pump arranged in the first power transmission mechanism and a second one-way clutch allowing only power transmission from the engine to the oil pump arranged in the second power transmission mechanism.